1. Field of the Invention
The present invention is directed to a printer or copier device system for performance-adapted production of a predetermined sheet sequence of monochromatically and/or chromatically printed single sheets, and is also directed to a printing method for producing a monochrome and chromatic sheet sequence.
2. Description of the Related Art
There is the problem in electrophotographic color printers having high print quality as known, for example, from European Patent Document EP-A1-0 629 931 that the same time is always required for producing a printed sheet both in monochrome printing mode as well as in chromatic printing mode. This means that what is referred to as the performance, i.e. the speed efficiency of the printer, is based on the full-color printing. When such a printer is utilized in mixed mode, then it is too slow for the usually occurring monochrome printing.
In electrophotographic high-performance printing with 70 pages per minute or more, the print jobs to be processed contain a majority of monochrome printouts. Only a small part of the print job is chromatic. For example, it can thus occur that a multitude of black-and-white successive sheets are printed within a print job and that one full-color image must be printed out then, for example when producing a brochure. When the usual color printing devices are utilized when producing such a brochure, these are relatively slow since, as already stated, the printing performance is based on the color printing performance. Such color printer devices are also complicated and cost-intensive and inefficiently utilized for mixed mode.
Color printer devices with which single-color or two-color printing can be carried out at high speed are disclosed, for example, by U.S. Pat. No. 5,526,107. In the known color printing means, continuous form paper is supplied to a transfer printing location of a photoconductor cylinder that respectively comprises electrophotographic units on two surfaces for producing multi-colored toner images. The continuous form paper is printed on the front side with a first color at the transfer printing location; the continuous form paper is subsequently redirected and supplied to a printing location at the same photoconductor cylinder that lies opposite the transfer printing location and the backside is printed thereat.
U.S. Pat. No. 5,596,416 discloses a printer device wherein a plurality of identical color printer means are arranged. Each of the color printer means is suited for monochromatic and color printing, whereby a parallel processing of images to be printed is possible.
What all of the known color printer devices have in common is that their performance is based on the color printing and, therefore, that the printer devices are uneconomically utilized for the mixed mode.
An object of the invention is to offer a multi-color printer or copier device system having high printing performance that is especially suited for the mixed mode and whose performance is based on the maximum printing performance in the monochromatic mode.
This and other objects are achieved by the inventive method of producing a predetermined sheet sequence of single sheets printed monochromatically and/or multi-colored in a printer or copier system, including
a) printing a first sequence of recording media at a first speed on one side or both sides monochromatically or in two colors in a monochromatic or highlight printer unit with appertaining paper transport channel that can be individually driven and is fashioned as an independent structural unit;
b) printing a second sequence of recording media on one side or both sides in full color in a color printer unit with appertaining paper transport channel that is individually drivable and fashioned as an independent structural unit, being printed with a second, lower speed compared to the first speed;
c) the first and/or the second sequence of recording media being accepted by a paper path coupling module connectible to the paper transport channels of the monochromatic or highlight printer unit and of the color printer unit;
d) producing the sheet sequence of the recording media from the first and from the second sequence of recording media and supplying the sheets to a shared sheet collector and/or post-processor in a predetermined sequence; and
e) separating incoming print data into monochromatic and color print job data with a synchronous control and communicating the respective print job data to the corresponding printer units. The objects are the invention are provided as well as by the printer or copier system for producing a predetermined sheet sequence of single sheets printed monochromatically and/or in full color, the system including:
a) an individually drivable monochromatic or highlight color printer unit with an appertaining paper transport channel fashioned as an independent structural unit for single-sided or both-sided printing of a first recording medium as a monochrome or as highlight color print with a first speed;
b) an individually drivable color printer unit with an appertaining paper transport channel fashioned as an independent structural unit for single-sided or both-sided, full-color printing of a second recording medium with a second, lower speed compared to the first speed;
c) a paper path coupling module connectible to the paper transport channels of the monochromatic or highlight color printer unit and to the color printer unit that accepts the printed first and/or second recording media and supplies them to a shared sheet collecting means and/or post-processing means for the sheet sequence; and
d) a synchronous control means connected to the monochromatic or highlight color printer unit and to the color printer unit, with which incoming print data can be separated into monochromatic and color print job data and the respective print job data can be communicated to the corresponding printer units. Advantageous embodiments of the invention are provided by the method above, whereby the sequence of the recording media in the sheet sequence is predetermined by a print data stream that contains monochromatic data and/or highlight data on the one hand and, on the other hand, color data, whereby the monochrome data or the highlight color data are supplied to the monochromatic or highlight printer unit and the color data are supplied to the color printer unit, and the sheet sequence is produced by an electronic controller according to the print data stream. The printer units and the paper path coupling module are driven time-organized by a synchronous control means, taking the printing speeds of the printer units and the sequence of the sheet sequence into consideration, such that the production of the sheet sequence ensues speed-optimized given largely parallel operation of the printer units. The recording media are printed in advance in the color printer unit, are then stored in a buffer store and are supplied time-exactly into the sequence of the recording media of the monochromatic or highlight color printer unit.
In the printer or copier system above, the monochromatic or highlight color printer unit may be a single sheet printer unit, and whereby the sequence of recording media from the color printer unit can be supplied into the output region of the monochromatic or highlight printer unit. The sheet sequence from the output region can be optionally supplied to a device output or to an internal stacking means of the device. The synchronous control controls the printer units and/or the paper path coupling module taking the printing speeds of the printer units and the sheet sequence into consideration, such that the production of the sheet sequence ensues speed-optimized given far-reaching utilization of a parallel operation of the printer units. In a preferred embodiment, the synchronous control is connected to the paper path coupling module and/or to a print data source. The sequence of the recording media from the color printer unit can be supplied into the input region of the monochromatic or highlight color printer unit.
At least one transfer printing station, an appertaining transfer printing transport path and a special paper path is provided in the monochromatic or highlight color printer unit via which sheets can be transported directly from the input region to an output region bypassing the transfer printing stations and/or the transfer printing transport path of the monochromatic or highlight color printer unit. The synchronous control comprises a device controller of the monochromatic or highlight color printer unit and a device controller of the color printer unit that may be coupled to one another according to the master-slave principle for controlling the sheet sequence. In one embodiment, the device controller of the monochromatic or highlight color printer unit is the master.
A controllable buffer storage is functionally allocated to the paper transport channel of the monochromatic or highlight color printer unit and/or to the color printer unit for the corresponding recording media. The buffer storage is arranged in the paper transport channel of the paper path coupling module.
The printer or copier device system above may include a synchronous control having the following features:
both printer units comprise a data controller, whereby the printer units are in communication with one another in the sense of a master-slave coupling;
a job separator is provided that, on the one hand, separates the incoming print data of an external data source into monochromatic and chromatic print job data, whereby, for sequence administration, each printed page comprises a specific address or feature and the respective print job data are then communicated to the corresponding printer units, and that, on the other hand, forms sequence data allocated to the sequence of the single sheets and communicates these to the printer unit having the master function, whereby the printer unit having the master function controls the other printer unit and/or the paper path coupling module for producing the sheet sequence.
Alternately, the printer or copier device system has a synchronous control means having the following features:
one of the two printer units comprises a data controller shared by both printer units;
the data controller has a job separator allocated to it that, on the one hand, separates the incoming print data of an external data source into monochromatic and chromatic print job data wherein, for sequence administration, each printed page comprises a specific address or feature, is and that, on the other hand, forms sequence data allocated to the sequence of the single sheets, whereby the printer unit with the data controller controls the other printer unit and/or the paper path coupling module for producing the sheet sequence.
One of the two printer units may be fashioned as an insert means for acceptance and output of pre-printed single sheets. The paper path coupling module supplies the printed recording media to the paper transport channel of the respectively other printer unit such that it can be additionally printed by the accepting printer unit. The printer units are preferably fashioned as independently operable electrographic printer devices.
As a result of the provided coupling of a digital monochromatic printer working at high printing speed, for example a black-and-white printer or a maximum of a printer printing in two colors (highlight color printer), with a digital full-color printer, mixed print jobs wherein the sheet sequences contain individual color pages can be produced at high speed and especially economically.
A higher-ranking control unit designationally sends the pages to be printed to the respective printing unit and assures that the correct, alternate page sequence is produced in a common paper output stream.
It was inventively recognized that the electronic and mechanical coupling of the monochromatic or highlight color printing units on the one hand and of the full-color printing unit on the other hand makes it possible to produce mixed printing jobs that comprise monochrome or highlight color data on the one hand and, on the other hand, comprise full-color data, producing these print jobs with high performance and with a high degree of utilization of the two printing units.
The control unit controls the printer units in the production of the mixed printing job dependent on the incoming data stream such that both printing unitsxe2x80x94insofar as the sequence of the individual sheets in the print job allows itxe2x80x94work in parallel mode. The desired control and drive objective is of the control is the parallel mode.
To this end, the monochrome (black-and-white) and the chromatic information from an original data stream are allocated to the respective printing unit and organized in terms of time. The shared paper path then conducts the printed single sheetsxe2x80x94correctly sortedxe2x80x94into a shared deposit (for example, externally, in the output compartment of the fast monochromatic printer, in the output compartment of the color printer) or into a post-processing system in the form of a sheet/steam/or packet stream. One of the digital printer or digital copier machines having printing function can thereby also assume the collecting function on the basis of its internal paper path and/or can generate additional printed information on the delivered sheet (for example, color on the front side, black-and-white on the backside or some other arbitrary combination). The interfaces are fashioned such that the printers or copiers can be utilized according to the respective performance demands of the operator. In order to smooth different performance peaks (for example, a high sequence of monochromatic or chromatic pages), the shared paper path can contain a buffer function. The buffer function can be realized, for example, by a collecting compartment from which the printed sheets are in turn output as needed individually or in packet form. The paper path itself can be utilized as a buffer on the basis of its distance. Buffers in the form of paper loops are known for printers that process continuous form paper. The productivity of the system is enhanced by the buffer function.
Both single sheet printers (cut sheet printers) as well as printers that work with continuous form paper (fan-fold printer) can be utilized as printing units. The use of cutting devices is required given fan-fold printers.
The sheet stream produced by the color printer in a preferred exemplary embodiment is introduced into the output region of the monochromatic or highlight color printer via a suitable interface, for example via a paper path coupling module. Therein, the chromatically printed sheets are inserted in proper sequence into the sheet stream printed by the monochromatic or highlight color printer. The monochromatic or highlight color printer in this embodiment serves as a mixing means (or merging means). It is advantageous given this embodiment that the high-speed printing mode in the monochromatic or highlight color printing unit is not deteriorated by the delivery of the sheets printed in full color.
In another, advantageous exemplary embodiment, the sheets printed in full color are kept on hand in an intermediate storage. The intermediate storing makes it possible to print the full color pages in advance and to then designationally feed them into the sheet stream of the monochromatic or highlight color printing unit. Despite a slower printing speed of the full color printing unit compared to the monochromatic or highlight color printing unit, the printing speed of the overall system remains high given mixed printing jobs. The intermediate storage can ensue in the full-color printing unit or in the monochromatic or highlight color printing unit but preferably ensues in a paper path coupling module connected between the printer units. It can ensue via a stacked intermediate deposit of the sheets or via a corresponding buffer transport path that accepts a specific number of single sheets.
In another preferred exemplary embodiment, the sheet stream produced by the color printer is introduced into the input region of the monochromatic or highlight color printer via a suitable interface, for example, via a paper path coupling module having an intermediate storage. Within the monochromatic or highlight color printer, the sheets printed in full color are then optionally conducted past the transfer printing station and/or the fixing station, potentially a plurality of such stations, or are again printed therein monochromatically or in two colors at high speed. The sheets printed full-color are thereby inserted into the sheet stream printed by the monochromatic or highlight color printer.
The invention is especially advantageous in conjunction with a highlight color printer; applications, namely, having a high proportion of two-color prints are becoming more and more frequent in the field of electrographic high-performance printing. The page costs as well as the printing performance are then especially beneficial in an inventive printing system, namely high performance at low cost.